For the meatballs: Combine the turkey, shallot, panko, Parmesan, egg, parsley, red pepper flakes, salt and pepper together in a large bowl and mix well. Shape the mixture into the size of walnuts and place in a single layer in a 13-by-9-inch casserole dish.

Pour the sweet and sour sauce over the meatballs, cover with foil, and bake for 35 minutes. Remove the foil and bake 10 minutes more. Serve with decorative bamboo toothpicks.